Precision wire electrochemical machining of thick structures in powder superalloy René88DT using a partially insulated tube electrode

Wire electrochemical machining(WECM)is a potential method for manufacturing macrostructures from difficult-to-cut materials,such as turbine slots,with good surface integrity and low costs.In this study,a novel tube electrode with array holes in the front and insulation in the back was applied using WECM to improve the machining precision and efficiency.Additionally,assisted by an immersion electrolyte and axial flushing,the electrolyte-deficient gap was supplemented to achieve the cutting of a very thick workpiece.The simulation results indicated that this method could effectively reduce the machining gap and improve the uniformity of the electric-and flow-field distributions.Experiments verified that when the uninsulated range(machining angle)was reduced from 360°to 90°,the side machining gap was reduced from 462.5µm to 175µm.Finally,using optimized machining parameters,array slits with gaps as small as(175±10)μm were machined on a powder superalloy René88DT sample with a thickness of 10 mm at a feed rate of 16µm/s.The feasibility of fabricating complex profiles using this method was verified using a self-designed servo device.

Wire electrochemical machining with axial electrolyte flushing for titanium alloy

Titanium and its alloys have found very wide application in aerospace due to their excellent characteristics although their processing is still a challenge. Electrochemical machining is an important issue in the fabrication of titanium and titanium alloys. Wire electrochemical machining （WECM） is mainly used for workpiece cutting under the condition of different thickness plates. It has a great advantage over wire electro-discharge machining, which is the absence of heat-affected zone around the cutting area. Moreover, the wire electrode in WECM could be used repetitively because it is not worn out. Thus, much attention has been paid to WECM. The effective way of removing electrolysis products is of importance to WECM. In this paper, the axial electrolyte flushing is presented to WECM for removing electrolysis products and renewing electrolyte. The Taguchi experiment is conducted to optimize the machining parameters, such as wire feedrate, machining voltage, electrolyte concentration, etc. Experimental results show that WECM with axial electrolyte flushing is a promising issue in the fabrication of titanium alloy （TC1）. The feasibility of multi-wire electrochemical machining is also demonstrated to improve the machining productivity of WECM.